If people hate each other enough, they feel a need to prove the other one wrong - so they do that on twitter and facebook, i.e. some 'red' person posts somethin

If people hate each other enough, they feel a need to prove the other one wrong - so they do that on twitter and facebook, i.e. some 'red' person posts something, 20 blue people attach them back, a 'blue' person posts something, 20 'red' people attach them back. When people are attacking each other online, they are engaged online - and the longer the stay online, the more ads they see, the more money facebook and twitter etc make.